Piezoelectric Spark Generator.

Piezoelectric spark generators create electricity when PZT (Quarts crystal) is deformed by the sudden hit of a hammer on rails.
The generators can be found in thumb-friendly lighters, BBQ lighters, built-in BBQ igniters and other spark ignition systems.

The spark doesnt hurt that much ? I’ve given sparks to my teeth with these
sparkers.. I think it hurts the most to the teeth. Teeths are moist and it
goes to the nerves inside or to gums.. But even that doesnt hurt so much.
Some people are so afraid of these little sparks and can’t even take one
into the hand.. It’s not like it’s a tazer !﻿

James Omosanjo OLADEJO you are saying free energy but how you describe
efficiency of this spark generator if it 80 % efficient enough than it is
used to recharge the rechargeable battery or not formula behind the working
of this device is any body give full description﻿